<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <button>1</button>
</body>
</html>
<script>
    var but=document.querySelector('button')
    but.addEventListener('click',function(){
        alert(11111)
    }, true)
    but.addEventListener('click',function(){
        alert(2222)
    }, true)
</script>